Effects of Seedbed Density and Nursery Fertilization on Survival and Growth of White Spruce

Abstract

The effects of seedbed densities and fertilizer levels on growth in the nursery and on performance after planting of 3-0 white spruce (Picea glauca (Moench) Voss) were studied in an experiment started in 1965. Seedbeds were thinned at 1-0 to densities of 15 and 30 trees per ft 2 (161 and 322 per m 2 ). Fertilizer treatments consisted of 'control' (no further treatment after 1-0), 'normal' (the recommended level for top dressing from soil and plant analyses) and 'double' (twice the recommended amounts).Results five years after outplanting showed much benefit from thinning to 15 trees per ft 2 (161 per m 2 ) at both nurseries. Normal fertilizer applications at Midhurst gave small benefit over the controls but the double fertilizer gave increased growth (aggregate height) up to 15%. At Orono the normal fertilizer treatment gave more benefit but doubling it gave only a small additional increase. The need for field test plots to study the effectiveness of the fertilizer program is stressed.